Idles rough once it starts to warm up and cuts off after it gets warm.

Tiny
KANE29360
  • 1993 FORD F-150
  • 78,000 MILES

5.8 ford f150 1993. I have replace plugs, wires, map sensor, and the iac and fuel filter and it still runs bad. It act likes it is getting to much fuel now. U can put ur hand at the tail pipe and oncw u remove ur hand it will smell like straight up gas. What else could cause it to be like this? Could it be an o2 sensor, bought bad plugs, or what? It really driving me crazy.

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Sunday, April 28th, 2013 AT 7:31 PM

11 Replies

Tiny
HMAC300
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Scan for codes and check fuel pressure first then check for a vacuum leak

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Monday, April 29th, 2013 AT 7:23 AM
Tiny
KANE29360
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If its getting to much fuel then how I go about fixing it?

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Monday, April 29th, 2013 AT 7:37 AM
Tiny
HMAC300
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Check your pressure first not "that it's getting to much fuel". It can either be a pump or regulator. Unless you decide to use the shotgun approach and spend money unnecessarily on parts that may not fix it. You've done that already. Fp should be 30-45 psi engine running or 35-45 key on engine off

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Monday, April 29th, 2013 AT 7:44 AM
Tiny
KANE29360
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The fuel pressure regulator is mounted on the fuel rail isn't it? Has 3 bolts and the vacuum hose running from it the intake right?

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Monday, April 29th, 2013 AT 9:30 AM
Tiny
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Yes

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Monday, April 29th, 2013 AT 9:35 AM
Tiny
KANE29360
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Okay. I just wanted to make sure. Thank you. I will try an see if this is the problem after I check the codes.

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Monday, April 29th, 2013 AT 9:38 AM
Tiny
KANE29360
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Fuel pressure is fine and I changed the fuel regulator and checked for vacuum leaks and there is no leaks. What else could it be?

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Monday, April 29th, 2013 AT 6:09 PM
Tiny
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Fuel pressure is fine? What is fine? How much psi? Scan for codes as well. It cold be leaky injectors but you need to eliminate everything else

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Tuesday, April 30th, 2013 AT 5:34 AM
Tiny
KANE29360
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Its has around 32 psi when its off and around about 36 with key on.

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Tuesday, April 30th, 2013 AT 8:51 AM
Tiny
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Originally I said scan for codes so do that and look at spark plugs if wet throw them away and replace them it may start like that. It can also be bad injectorsbut I dont' have any specs for them to check for resistance. Other than that not seeing this vehicle I couldn't tell ya what else to do.

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Tuesday, April 30th, 2013 AT 9:49 AM

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